<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<mce:script language="javascript" type="text/javascript"><!--
function insert(){
var theDoc = document.getElementById('fr1').contentWindow;
//theDoc.style.display = "block";
//theDoc.document.open(); //会自动打开
//theDoc.document.designMode = "on"; //会自动打开
theDoc.document.write('<html><head>');
//theDoc.document.write('<meta http-equiv="Content-Type" content="text/html; charset=utf-8">');
theDoc.document.write('</head><body width="100%" contentEditable=true style="padding:0;margin:0; overflow:hidden;" mce_style="padding:0;margin:0; overflow:hidden;">');
theDoc.document.write("lfasjdfkjalsejioruw fskdjfla;sjdkjfsahgasjdla;kjeioujrfhfaksdjfjal;skdjfhgsadlkfjla");
theDoc.document.write('</body></html>');
theDoc.document.body.contentEditable="false"; //要显示关闭可以编辑状态，不然内容是可以编辑的
//theDoc.document.designMode = "off"; //没用
//theDoc.document.close();
}
// --></mce:script>
</head>
<body>
<input type="button" value="insert" onclick="insert();" />
<iframe id="fr1" width="200" height="200" ></iframe>
</body>
</html>
原文地址:http://blog.csdn.net/ikmb/article/details/5973383